Tests

J.-M. Bruel
jbruel@gmail.com
version 1.0 2017-03-12

Materials in live…​

http://bit.ly/jmb-agile

http://jmbhome.github.io/teaching/topics/agile.html

Tests

Whatever development method you apply, tests are the only way to ensure that the delivered product conforms to the client’s requirements.

Unit Tests

They are the simplest. But hence it is needed to …​

  • forget 'manual' approaches
  • explore their 'limitations'
  • treate both the 'qualitative' and 'quantitative' aspects

Unit Tests

Let’s consider the implementation of an abstract type: MatrixInt

Unit Tests (operations)

  • Operations

    • createMatrix : Int * Int → MatrixInt
    • getNbLines: MatrixInt → Int
    • getNbColumns: MatrixInt → Int
    • …​

Unit Tests (preconditions)

  • Preconditions

    • createMatrix(l,c) valid IF and ONLY IF ( l > 0 ) AND ( c > 0 )
    • getElement(m,i,j) valid IF and ONLY IF ( 0 < = i < getNbLines(m) ) AND ( 0 < = j < getNbColumns(m))
    • …​

Unit Tests (axioms)

  • Axioms

    • getNbLines(createMatrix(l,c)) = l
    • getNbColumns(createMatrix(l,c)) = c
    • getElement(createMatrix(l,c),i,j) = 0
    • isSquared(createMatrix(l,c)) IF and ONLY IF l = c
    • …​

Unit Tests (testing operations)

src/MatriceEntierOperationsTest.java

Unit Tests (testing preconditions)

src/MatriceEntierPreconditionsTest.java

Unit Tests (testing axioms)

src/MatriceEntierAxiomsTest.java

Unit Tests (testing additional operations)

src/MatriceEntierOpSupTest.java

Unit Tests

The testing program is :

  • a regression detection tool

    • that should be run on each modification of the MatrixInt class

  • a specification documentation

    • precise AND concise

  • a programmers' documentation

    • operational

Integration Tests

titanic

Integration Tests

no integration testing

Integration Tests

It a more complicated activity. It is required to:

  • test the client’s expectations/requirements
  • test systems' interactions
  • no redo the unit tests

Integration Tests

Testing program of JourSuivantAvecLibDate.class
import junit.textui.TestRunner;
import junit.framework.TestSuite;
import junit.framework.TestCase;
import java.io.*;

public class JourSuivantAvecLibDateTest extends TestCase {
  static String programmeATester = "JourSuivantAvecLibDate" ;  (1)
  Process executionProgrammeATester ;                          (2)
  BufferedReader ecranProgrammeATester ;                       (3)
  BufferedWriter clavierProgrammeATester ;                     (4)

  String finDeLigne = System.getProperty("line.separator") ;   (5)

  public static void main(String[] args) {
    if ( args.length > 0 ) { programmeATester = args[0] ; }
    System.out.println("Tests du programme : " + programmeATester);
    junit.textui.TestRunner.run(new TestSuite(JourSuivantAvecLibDateTest.class)); (6)
  }

  protected void setUp() throws IOException {  (7)
    executionProgrammeATester = Runtime.getRuntime().exec("java -cp . "+programmeATester); (8)
    ecranProgrammeATester = new BufferedReader(new  InputStreamReader( executionProgrammeATester.getInputStream() )); (9)
    clavierProgrammeATester  = new BufferedWriter(new OutputStreamWriter( executionProgrammeATester.getOutputStream() )); (10)
  }

  // Saisies valides
  public void test_31_1_2013() throws IOException {
    assertEquals("Affiche : 'Saisir une date : jour mois annee ? '","Saisir une date : jour mois annee ? ",ecranProgrammeATester.readLine()); (11)
    clavierProgrammeATester.write("31 1 2013"+finDeLigne); (12)
    clavierProgrammeATester.flush();                       (13)
    assertEquals("Affiche : 'Le lendemain du 31/1/2013'","Le lendemain du 31/1/2013",ecranProgrammeATester.readLine());
    assertEquals("Affiche : 'sera le 1/2/2013.'","sera le 1/2/2013.",ecranProgrammeATester.readLine()); (14)
  }
1 name of the app to be tested
2 Process = the running program
3 link to the display of the running program
4 link to the keyboard of the running program
5 portable carrier return
6 launching of all the functions starting by 'test'
7 function (re-)executed before each testing function AND launch the program to be tested
8 launching of the program
9 connect to the display
10 connect to the keyboard
11 read a line on the display
12 send a line to the keyboard
13 force the keyboard flush
14 read another line on the display

Tests implement simple algorithms

public void test_dates_invalids() {
  int[][] tabJeuDEssaiDatesInvalids = {  (1)
      {1,1,1581},{0,1,2013},{99,99,2099},
      {32,1,2013},{29,2,2013},{32,3,2013},
      {31,4,2013},{32,5,2013},{31,6,2013},
      {32,7,2013},{32,8,2013},{31,9,2013},
      {32,10,2013},{31,11,2013},{32,12,2013},
      {29,2,1900},{30,2,2000}
  } ;
  for ( int indice = 0, taille = tabJeuDEssaiDatesInvalids.length;
        indice < taille ;
        indice = indice + 1){
    int[] date = tabJeuDEssaiDatesInvalids[indice] ;
    assertFalse(date[0]+"/"+date[1]+"/"+date[2]+" est invalid"
    , LibDate.datevalid(date[0],date[1],date[2])); (2) (3)
  }
  bilanAssertions = bilanAssertions + tabJeuDEssaiDatesInvalids.length ;
}
1 given: in the following situations
2 when: when we check the validity of a date
3 then: we should get false

Can everything be tested ?

  • librairies
  • system interactions (concurrency, etc.)
  • network services
  • graphical interfaces (html, java, flash, etc.)
  • …​
  • MAY BE NOT, but try anyway!

All the strategies are exploitable

  • Write a program that run the tests
  • Write the tests of a given program
  • Code a feature AND add the corresponding test
  • Add a test AND integrate the corresponding functionnality (TDD)
  • Find back the balance between Program / Tesing Program

Most common mistakes in programming

http://blog.takipi.com/the-top-10-exceptions-types-in-production-java-applications-based-on-1b-events/?utm_content=buffer0c58b&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Ready for a quizz?

tuxteacher

Ready for a quizz?

QUESTION
socrative1

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